Filter washing system



6790/7 6. Short BY 02/ H. H. MARSH ETAL FILTER WASHING SYSTEM ApriE 3, 1951 Filed July 28, 1947 April 3, 1951 H. H. MARSH EI'AL FILTER WASHING SYSTEM 2 Sheets-Sheet 2 Filed July 28, 194'? ATTOR/Vf) ing liquid will be filtered by the filter bags upon which the filter material has been previously deposited.

After continuous cleanin of garments by the dry cleaning system the filter material on the filter bags will become dirty and contaminated and it will be necessary to clean these bags and have :1 deposited thereon clean filter material. In the past it has been customary to remove the filter v bags and screenforms and scrape the dirty filter material off the bags and then'wash the bags, or to provide some kind of a mechanical scraper in the filter tank for scraping the dirty filter material off the surfaces of the bags, or a mechani-,.

\ cal shaker arrangement. These methods of "-cleaning the filter bags have not proven satisfactory, since the scraping operation will result i in the dirty filter material being forced into the pores of the woven fabric of the bags and its re- 3 moval then becomes difficult. Also. the mechanical arrangements may easily become damaged due to the filters becoming bound in accumulate muck in the bottom of the tank.

is provided with a fairly large outlet opening to which is connected a pipe 26 leading to a settling tank2l. The pipe 26 is provided with a hand operated cut-off valve 28 so that it can be closed, except when filter material is desired to be removed from the tank. The settling tank has two compartments 29 and 30 separated by a low partition 3|. The drain pipe 26 enters the bottom part of the compartment 29 at a point below the partition 3! and thus liquid and the dirty filter material coming from the filter tank will collect in the bottom of the compartment 29 where it will settle out. Since this filter material is fairly heavy, it will settle out quite rapidly and relatively clear liquid will flow over the top of the partition into the compartment 33. If desired, a filter screen and bag 32 may be positioned between the compartments, as best shown in Figure 6, so as to aid in=preventing excessive filter material from being carried into the compartment 3!]. The compartment 33 has its lower portion connected by a conduit 33 to the inlet of In accordance with our invention, we have as sociated with the filter tank an improved filter cleaning system whereby the filter material deposited on the surface of the filter bags can be efficiently removed by washing without the necessity of scraping the bags or removing the bags from the filter tank. Associated with the top of the filter tank there is an auxiliary chamber ll 'havin for its top wall the convex top wall l8 of the filter tank and for its bottom a concave wall I9. This chamber I! is arranged to be sup-. plied with liquid under pressure from the previously referred to pump 3 by providing a conduit 20 leading from the conduit 8 to the chamber [1. The conduit 20 is provided with a hand cut-off valve 2|. The bottom [9 of the auxiliary chamber is provided with a plurality of outlet pipes '22 which are connected at the lower end with spray pipes 23. The number of outlet and spray p pes 23 are such that there will be a spray pipe positioned between adjacent filter screens and bags and also on the outside of each outer bag. The spray pipes 23 are horizontally arranged and of such length as to be co-extensive with the width of the filter bag, all as best shown in Figure 4. i The spray pipes are each provided with a 'plurality of longitudinally arranged spray or jet openings 24 so positioned in the pipe that liquid will be directed onto the upper portions of the surfaces of the filter bags at an acute angle and in a downward direction. In place of the spray pipes, any other suitable sprays can be employed.

' Since the liquid being sprayed by the pipe sprays j is under pressure, the streams of liquid will engage the filter material deposited on the surface of the bag and cause it to be peeled off the i surface of the bags. This peeled off filter mai terial will then move by gravity, or be washed with the liquid to the bottom of the filter tank below the outlet manifold. Y r

In order that the removed dirty filter material which goes to the bottom of the filter tank may pass on out of the tank, the bottom of the tank the pump 3 so that the liquid in this chamber can be re-circulated during the washing operation and also to permit clarified liquid to be pumped back into the cleaning system for reuse. The conduit 33 is provided with a hand valve 34.

To perform the filter washing operation the cleaning washer I will be disconnected from the filter tank by closing the valves 6 and I0 and the pump will be disconnected from the top of the filter tank by closing the valve 9. The valve 2| will be opened so that the pump can supply liquid through the conduit 26 into the auxili'ary chamber I! at the top of the filter tank. Also, the valve 28 of the drain pipe will be opened so that the bottom of the filter tank will be connected with the settling tank. When the drain pipe is open, all the liquid in the filter will be drained out in the settling tank 21 which should be of such capacity as to hold more liquid than the filter tank. The incoming liquid will rise to' a level above the wall in both chambers. When the liquid is drained from the filter through the drain pipe, it will carry out accumulated muck from the bottom of the filter tank and this muck will settle out in the bottom of the chamber 29. When the tank is drained there will be some gas pressure in the tank which will keep the tank empty. If the pump 3 is now started, liquid can be forced into the chamber I! under pressure. This liquid may be taken either from chamber 39 of the settling tank through conduit 33 by openingvalvc 34, or it can be taken from the storage tank through the conduit IS. The liquid under pressure in the chamber 11 will be conducted into the spray pipes 23 and forced in streams out of the holes 24 and onto the surfaces of the filter bags. The streams of liquid under pressure will then act to peel off the dirty filter material deposited on the filter bags and as it falls down into the bottom of the filter it will be washed out in othe chamber 29 of the settling tank. This washing will also insure that all accumulated muck in the bottom of the tank will be removed. During the washing process it will not matter whether the liquid being circulated contains small particles of filter material as such will do no harm during the washing process and the peeling off of the deposited filter material. The washing process to clean the filter bags will not consume an excessive amount of time, but it will vary some, depending upon the amount of filter material accumulated on the filter bags and also the tight- .-.top thereof merely byopening thervalvefifi whenfever-"such circulation may bede ired. Underzcer-z q 5 hess"oftheidepositiof filter' material. toen-er'ally washing. operation covering *fifteenfor twenty inu'tes "will be sufiicient-to completelyclean the lter'zba'gs. Under.no oircumstances" will it take 'ore'thanthirtyztdthirtwfive minutes. During washing the 'jpumpd liquid pressure "shouldbe "far'ourid'or above "fourpoundsper square inch. menithe 'filter washing "operation is completed .thevalvef'28in the 'drainpipe and'the' valve 21 in will be closed and the .valves 6, Stand llliopened liso' asto reconnect the ,pumpsand washer I to the Tjifiltertank. "Thefiltertank canthen beifilled with 'l'ean'liquidbythe use of thepump 3, this olean quid com'ing from the usual storage tank or" mm .thechamber 3B o'f'the-settling tarlk. Genrally the ifilter washing operation of .the .filter ags vizillbe accomplished. at .the :end 01 .thefday rid [the liquid employed during washing willbe;

onsequently the liquid. in the settling tank will'be ree -of' dirty filter material and it can be .re-used cm @the'system instead of a new supply from the the settling tank to fill the filter tank and washer, liitlcan be supplemented fromthe storage .tank. iiNewfilter material will beplaced in'the system 'a-andtas the pump circulates the liquid'and the sIfgdesired, the lower portion of the filter tank .below the outletmanifoldiand above the rbottom of-the tank can be connected by a conduit '35 the "conduit 1 leading to the inlet of theep. "Ihe conduitcanvbe controlledbycavalve 135. Thus liquid can -;be circulated by pump 3 -.--from the bottomportion'oi the filter tank to the stain conditions "the drain pipe 2252:1213}! become so ifilled with .muckand :dirty filter 1 material. dur- :ing :use of the "cleaning system that "when the valve -zq is opened, liouid and"filter materialscan ,inot be drained 'intozthesettling' tank. To clean 4 w thi's drain pipe .ofpac'ked' muck "andfilter'ma- 'terial, there .;'canbezprovided :a conduit .3? from the :outlet side of :thepump:.3 to the'drairrcpip'efifi aheadaof :the'valve 12.8. Thispondu'it canihayea valve 38. Thus by opening thevalve 38,i1iquid iunder pressure can be forced i into thexdrain pipe id-and with the valve Z8 "closed it rw'illpush the "fmuck accumulated :in :the drain ipipe 'iba'ck so that liouid" and 'mu'ck will flow' therethrou'gh whenth'e valve ztis opened.

With our improved '1 filter was'hing "system *a's-- 3'sociate'd with aa dry zcleaning -system embody g l a fi lter itank' Thaving filters, :it' is "seen that it is do any lfilter scraping or remove-the' filters. Also,

5.1 mechanical devices for agitating the filters are necessary. To :perform "the filter operation it is merely necessary "to close -certain-valves*to vilisconnect the washer fro'm th'e 'filter tank *afrid to --epen up other valves "so as *to connect the ipuznp into "the Lfilter washing-system. "The "-op'eratior-i 'of the -pump will then accomplish "the filter bag washing and the muck and dirty filter material will bedepos-itd in a settling tank where-it WflI ZO zireadilyfsettle' out during an interval of tim'e so as-te-per it re-use of the-liquid. The muck e'anddirty filter material which"settles inthe' bot- .t'om of "the compartments 2 9; and' -M of the setllowe'd' to. settle over night. .in' the settling tank.

entafter: therclearitliquid:hixthessettlingetankihas en pumpedsrbackiinto theoleaifingggystem. iiIf desiredg the settlin'g' tank be provided {any"fsuitablescoveriafllhaving movihg it. H

It is to be pa'rticularlyignoted ltha't intthe proved filte-r washing'i'sys'tem.xlisclosedxby wayx f exarnple zas embodying .IOUL invention, that iathe same pump cemployed 15in."cleaningisystemsiis lalso f u t1 dn 'to'the washin chamber W 7 p the con ea 1 g g "'system is easily adaptedsforassociation withany employed in t the washing :system. The washing types of 'filters. The washing system .is 5a time savers'inceiduring title washingiintervaltno:operat'ors atte'ntioniis -required, i'thuszallowing theiop- 5 erator to .performntheriduties. Neith'ert thesbottom' n'or top "-o'ffthe filter .tank'needs to be removed to perfor-m *the ifi-lter cleaning. All dirty filter li material and' muckw'ist removed from the filter "tank :and 'deposite'di-ini-a separate settling tank where it "can "be" removed conveniently. rR'emov- Ls'torage tank. If there isnot sufiicient liquid 111.11 'before'ithe r starte'd-and. du i g :wash

'gases from the washing liquid will maintain such a positive pressure in the -tank as .to prevent any return' fiow from' the settling tank to the'hlter tank because of difference in liquid -levels. 'The "filter material will be deposited on the cleaned;. System alsoprevems any accumulatmn .efilter bags in'a manneralready noted.

of filter material in the storage tank. 'The liquid to be reured is clarified 1 the zsettling tank. With the improved washing system it-is also possible to drain muck from the' filtertankduring operation of the cleaning system. If, duriinga days run, an excessive amount offmuck accumulatesfin the bottom of the filter'tank, ithe drain pipe can be opened for a short period:of time, thus allowing'some liquid and .muck to .enter the settling tank. The liquid passing out with the fmuck can be replaced 'from the storage tank.

In.Figure 7' a modified structure for washing "the filter bags is disclosed. In the topof the filter tank 2 there is provided a washing chamber l1 formed by the top wall i8 of the'filter tankand a :concave bottom wall [9. In place of the spray pipes 23 this bottom wall [9 :is provided withs'a plurality of holes 4| which are so drilled through the bottom wall as to direct liquid under pressure onto the filter bags at :an .acute angle so that it will be possible to wash the filter bags clean of deposited filter material. "Thus when theisystem conditioned so that liquid under pressure from the pump is supplied through the conduit .20 to the chamber 1], this liquidwill .Another way in which .the washing of the filter screens can beaccomplished is shown in'Figure 8.

. Intheztop of the filter tank 2 there is formed a separate washing chamber '42 "which 'is arrangedito be movable relatively tothe-filtertank.

The chamber is for-medby an -imperforate"convex top wallAi-landa concave bottom wall ll-provided with a plurality of perforations or'jet holes 45. The -wash-ing liquid-under pressure 'is supplied'toth'e chamber '42 through a pipe20 which is somounted in the side-wall of the filtertank bysmeans of packing gland bearing 46 that it '-.xcantact asa pivotal :shaft. Diametrically opposite the -inlet pipe-2 0 the chamber provided In using this washing artank to give the perforated bottom wall 44 of the chamber a rocking or swinging movement so that the streams of liquid coming from the chamber through the perforations can be directed in various directions. The perforations in the bottom wall can be made so that when the chamber is in a normal horizontal position the streams of liquid can have a directly downward flow and when it "is desired to cause these streams to be directed at an angle onto the surfaces of the filter bags,- the bottom wall can be shifted by moving the handle 49. perforations can be directed so as to clean like sides of the filter bags and by a shift of the cham- Thus the streams coming from the ber the streams can be directed to clean the opposite sides of the filter bags.

Being aware of the possibilities of modifica tion in the various structures disclosed by way ,of example without departing from the fundamental principles of our invention, it is not intended that the scope of the invention be limited in any manner except in accordance with the appended claims.

What is claimed is:

1. In combination with a cleaning systemcomprising a cleaning washer, a fil er tank having spaced filter structures vertically mounted therein and upon which filter material is deposited, a pump, an inlet, an outlet and conduits for circulating cleaning liquid from the pump to the filter tank to the washer and back to the pump, of a filter washing system comprising a valve controlled drain pipe from the bottom of the filter tank separate from the tank outlet,

means for supplying liquid under pressure from the pump to the top of the filter tank independently of the inlet and for spraying said liquid onto the filter structures, and means for supplying liquid from the pump to the drain pipe ahead of the valve thereof.

2.In combination with a filter tank containing spaced vertically arranged stationary filter structures extending substantially across the tank and upon which filter material is deposited and having associated therewith a liquid circulating system including a pump connected to supply liquid to, the top the filter ot a drain conduit connected to the bottom of the filter tank, means providing a liquid chamber above the filter structures, means for supplying liquid I under pressure to the chamber, stationary spray pipes positioned between the filter structures and j on the outside of the outer filter structures and extending substantially the width of the filter structures for directing streams of liquid onto the surfaces thereof adjacent the top ends, and

. means for supplying liquid to the spray pipes from the chamber.

- 3.111 combination with a filter tank having --tom of the filter tank, means comprising a. wall belowthe top wall of the tank and co-extensive therewith to thereby provide with the top wall a liquid chamber above the filter structures and extending over substantially the wholearea covered by-the top edges of the filter structures, said last named wall being provided with spray openlugs, and means for supplying liquid under pressure to the chamber to thereby cause liquidto be sprayed in a downward direction ontov the filter structures.

l 4. In combination with a filter tank containing spaced vertically arranged filter structures upon which filter material is deposited and having associated therewith a liquid circulating system including a pump connected to supply liquid to the top of the filter tank, of a drain conduit connected to the bottom of the filter tanlgmeans providing a single liquid chamber above .and of a size to extend over the filter structures and provided in its bottom wall withspray openings, said' bottom wall of the chamber beingof an area to cover substantially all of the top edges of the filter structures, means for supplying liquid under pressure to the chamber to thereby cause liquid to be sprayed in a downward direction onto the filter structures, means for mounting the chamber for movement relative to the tank, and means for moving the chamber to thereby change the direction of the spray streams. 5. In a filter washing system for association with a filter tank having a top wall, an inlet'fand an outlet and being provided therein with spaced vertically arranged stationary filter structures the top portions of which are spacedfromthe top wall of the tank, a drain conduit from the bottom of the tank and being separate from the outlet, means providing a wall in the topportion of the tank co-eXtensive with and spaced below the top wall to thereby form with the top wall a'liquid chamber above the top portions of the filter structures and covering substantially the same area as covered by the said top portions, means for supplying washing liquid under pressure to the chamber independently of 'the'i'nlet, and means for spraying the washing liquid from the chamber in a downward direction onto the filter structures to thereby wash all of the said structures filter surface without the necessitiy of moving the structures.

6. In combination with a filter tank containing spaced vertically arranged stationary filter structures extending substantially across the tank and upon which filter material is deposited and having associated therewith a liquid circulating system including a pump connected to supply liquid to an inlet at the top of the filter tank, of a drain I conduit connected to the bottom of the filter tank,

means providing a liquid chamber above the filter structures and the inlet, means for supplying liquid under pressure to the chamber independent of the tank inlet of the circulating system and by the pump and a conduit from the circulating system, and means for spraying liquid from the chamber in a downward direction onto substantially the entire side surfaces of the filter structure adjacent the tops thereof so as to wash said surfaces without movement of the filter structures.

'7. In combination with a cleaning system comprising a cleaning washer, a filter tank having I spaced filter structures vertically mounted therein and upon which filter material is depositeda pump, an inlet, an outlet, and conduits for cir- 4laiins. c anin liq ids from he pump lath 9 10 filter tank to the washer and back to the pump, UNITED STATES PATENTS of a filter Washing system comprising a valve con-- Number Name Date trolled drain pipe from the bottom Of the fil fi 3 9 37 Kelly t 9 90 tank separate from the tank Outlet, & ch mbei' 1 19 79 Atkins Mar. 20 19 in the top of the tank above the inlet, and means 5 1,510,558 Sweet-Jami Oct 1924 for supplying liquid under pressure fIOm h 13393 5 tt Jan 29 1935 pump to the chamber 111 the top 0f the fil r nk 2 013 77 Wiesman Sept 10 1935 and for spraying said liquid from the chamber 29%096 Moran June 6: 1936 onto the side surfaces of the filter structures ad- 1037,1775 Matthews July 20 1937 W the top ends thereof 10 2,435,201 Cooperider Feb. 2, 1948 HERBERT H. MARSH. GLENN G SHORT FOREIGN PATENTS Number Country Date REFERENCES CITED 629,059 France July 12, 1927 The following references are of record in the 15 file of this patent: 

